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This example shows a common align problem and a possible strategy to solve it.This is the set of meshes I have to align.

Note: For this description the partial results aren't native scans but parts of a split up already modified fusion result. I made this nonsense just to demonstrate that you might run into this problem even with perfectly fitting meshes.

To demonstrate the problem I align mesh 2 to mesh1, mesh3 to mesh2, mesh4 to mesh3 aso.

Aligning a set of meshes just along the order you grabbed the scans (e.g. clockwise) isn't ideal in this case for a still unknown reason.

A better strategy than this is a basic rule:Align the partial results along their dominance of topology.The target for the first alignment should be the one with the most details.In this case this is mesh1.So I align mesh2 to mesh1 and mesh7 to mesh1.Now also mesh3 to mesh2 and mesh6 to mesh7.That works fine.Also aligning mesh5 to mesh6 isn't any problem.

but the remaining mesh4 shows the either trouble. Using FreeAlign it is aligned faulty:

Starting the alignment at the center of the face has another advantage: IF the scans don't align perfectly (distorted scans), the important face region will look nice and bad alignment at the back can be retouched more easily.

Making a copy of a scan, then deleting all that is irrelevant for alignment, is similar to another idea we still have not had time to implement : marking relevant contact areas with a brush (mouse).

Starting the alignment at the center of the face has another advantage: IF the scans don't align perfectly (distorted scans), the important face region will look nice and bad alignment at the back can be retouched more easily.

Making a copy of a scan, then deleting all that is irrelevant for alignment, is similar to another idea we still have not had time to implement : marking relevant contact areas with a brush (mouse).

Sven

Hi Sven,

sure, some way to select some AreaOfInterest would be great. Basically the shown way is nothing else... But as long as you do not find the time to implement such stuff: There's a way to solve such problems with current tools.Maybe another idea:DAVID is able to ignore the scan's borders at a set range for alignment. Means there is already some algorythm to detect borderfaces and their neighbors. What if you'd implement a second limit (means: IGNORE faces nearer than parameter1 AND farer than parameter2 away from the scanborders). This should give the same result as I did manually above. This restriction should exclude a large portion of the surface to be aligned....

Hello Gunter,Thanks to share the trick. It is good one.I've tried a similar way time ago, and I can confirm that it works nicely. Just make longer the jobs, especially if we have many of them to align.So... we can just wait the "SelectRelevantContacts" function.